A chemical attack on history
The Etruscan necropolises at Tarquinia hold some of the most significant pre-Roman paintings in the Mediterranean. These bright frescoes, dating from the 7th to the 3rd centuries BCE, are under a slow, persistent chemical attack. The tombs are subterranean chambers, or hypogea, carved directly into the local volcanic tuff, a porous rock. This geology is important to both their preservation and their current decay.
Modern agriculture in the surrounding region uses nitrogen-based fertilizers. Rainwater carries these chemicals from the fields into the soil, altering the local groundwater chemistry. As this slightly more acidic water percolates through the porous tuff, it dissolves calcium carbonate (calcite) from the rock matrix. Inside the tombs, this calcite-rich water seeps through the walls and evaporates, depositing a hard, opaque crust of recrystallized calcite on the fresco surfaces. This process, which obscures and damages the ancient pigments, has been measured to proceed at a rate of 0.1 millimeters per year. Other studies have identified that certain bacteria, such as Bacillus species that survive biocide treatments, can also be responsible for producing these damaging calcium carbonate layers.
The art being lost
The Monterozzi necropolis contains around 6,000 graves, with approximately 200 of them decorated with these detailed frescoes. The paintings record the life of the Etruscan civilization, which left behind very little written history. The artists applied their pigments—made from materials like iron oxides for reds and yellows, chalk for white, and charcoal for black—onto a thin layer of plaster applied to the rock walls.
The scenes are not morbid, they depict a bright world of aristocratic life, banquets, dances, athletic contests, and mythological figures. The Tomb of the Leopards, for instance, shows a lively banquet scene, while the Tomb of Hunting and Fishing portrays figures in realistic poses. These images are the most extensive gallery of ancient painting to survive from before the Roman Imperial era. The art shows clear influence from Greek culture, particularly in the late Archaic period (mid-6th to early 5th century BCE), suggesting a cultural exchange across the Mediterranean. As the calcite crusts grow, the details of this lost world are progressively being hidden, turning colorful scenes into monochrome, crystalline surfaces.